Abstract: A portable electronic apparatus is disclosed having an antenna and a communication circuit. The antenna impedance is chosen to be a predetermined value which is deliberately mismatched to the impedance of the communication for a predetermined frequency band. This mismatch is chosen to optimize the signal loss between the antenna and the communication circuit when the antenna is far and near a disturbing source. The imaginary part of the antenna impedance has a sign opposite to the sign of the circuit impedance when the antenna is a predetermined distance from the disturbing source.

Abstract: A radio transmission system is disclosed for operating in a multipath transmission environment having improved reception, and in the case of bi-directional systems, also improved transmission. This is achieved by using at least two reception beams, corresponding to one fixed reception beam and one scanning reception beam, and by continuously evaluating the quality of these beams as to their signal-to-noise-and-interference ratios or bit-error-rates (BERs). The best beam is dynamically chosen to be the fixed beam. Alternatively, the fixed beam is updated with the best beam acquired by the scanning beam as compared to the current fixed beam. In a bi-directional system, the receiving radio apparatus applies the direction of the best reception beam for transmission to the opposite radio apparatus.

Abstract: A radio transmission system comprises a phased-array radio apparatus for optimizing reception in a multipath transmission environment. In the phased-array radio apparatus, phase shifting is performed after down-conversion of received RF signals. Phase control and beam-forming are simple. By applying a zero-IF or low-IF receiver structure, the complete structure can easily be fully integrated.

Abstract: For audio and/or video or control signal transmission between two rooms in, for example, a house, inductive and/or capacitive transmitters and receivers are used which are installed on opposite sides of the partition or wall that separates the rooms. The signals to be transmitted may be applied or tapped from the transmitter/receiver by cables or by infrared transceiving diodes. The transmitter and receiver consist of, for example, two metal plates or two coils installed substantially opposite each other on opposing sides of the wall.